Search results for "Energy engineering"
showing 10 items of 1099 documents
Quantitative Characteristics of Information Society and ICT Industry in Latvia
2015
Abstract The article is devoted to statistical analysis of information and communication technology (ICT) industry in Latvia and the development of Information Society in the country. On the basis of statistical data comparison of Latvia with other European countries is made. This comparison shows that Latvia belongs to countries with very well developed Internet. On the other hand the statistical data points on the fact that it is necessary to increase the awareness of population regarding possibilities offered by using of ICT and e-Government.
From the Global Crisis to the National Crises: The Case of the European Union Countries
2013
Abstract The aim of this paper is to examine the way in which the 2007 global financial crisis has emerged into more specific national ones. The interventionist policies responses have led to an intensification of the economic unhealthy situations in some countries of the European Union. At the same time through well-chosen economic policies other countries, managed to escape from the threat of collapse of their national economies.
Travel and Tourism as a Driver of Economic Recovery
2013
Abstract Nowadays countries are trying to overcome the adverse effects of this crisis but have failed to recover their positions due to severe recession and worsening economic conditions. Tourism can be one of the pillars that should be supported by governments around the world as part of the solution to stimulate economic growth. The paper examines the economic impact of tourism industry worldwide and with a focus to Romania. It also advances some solutions for the design of a more effective and efficient policy framework in order to take a proactive stance in tailoring policies and development of the tourism sector.
Stability analysis of load frequency control for power systems with interval time-varying delays
2023
This study investigates the stability problem of load frequency control (LFC) for power systems with interval time-varying delays. The two categories of time delays, the lower bound being zero and non-zero, are considered. The systems can be described as time delay systems of load disturbances. First, an augmented Lyapunov–Krasovskii functional (LKF) is constructed. Some delay-dependent nonintegral terms and single integral terms are additionally introduced to make full use of the information on the system state variables and the time-varying delays. Second, to overcome the problem of nonlinear inequalities caused by the augmented LKF, the nonlinear inequalities are converted into linear ma…
Computational Screening of Doped Graphene Electrodes for Alkaline CO2 Reduction
2020
The electrocatalytic CO<sub>2</sub> reduction reaction (CO<sub>2</sub>RR) is considered as one of the most promising approaches to synthesizing carbonaceous fuels and chemicals without utilizing fossil resources. However, current technologies are still in the early phase focusing primarily on identifying optimal electrode materials and reaction conditions. Doped graphene-based materials are among the best CO<sub>2</sub>RR electrocatalysts and in the present work we have performed a computational screening study to identify suitable graphene catalysts for CO<sub>2</sub>RR to CO under alkaline conditions. Several types of modified-graphene frame…
Replacement of Vehicle Fleet with EVs Using PV Energy
2016
The diffusion of Electric Vehicles (EVs), the reduction of environmental pollution and the production of energy from renewable sources (RES), in particular photovoltaic system, wind farm, hydroelectric plants, bioenergy and geothermal plants are the principal aspects discussed in the world. For this reason, the goal of this work is to study for 2014 year in all Italy's Regions; the energy production obtained to photovoltaic systems (PV) and the possibility to use with different percentage this energy for recharge the electric vehicles. In particular, they have been considered different scenarios in function to the km travelled per year from the population. This paper examines the integratio…
Enhanced flexible algorithm for the optimization of slot filling factors in electrical machines †
2020
The continuous development in the field of industrial automation and electric mobility has led to the need for more efficient electrical machines with a high power density. The improvement of electrical machines’ slot filling factors is one of the measures to satisfy these requirements. In recent years, this topic has aroused greater interest in the industrial sector, since the evolution of the winding technological manufacturing processes allows an economically sustainable realization of ordered winding arrangements, rather than random ones. Moreover, the manufacture of electrical machines’ windings must be preceded by an accurate design phase in which it is possible to evaluate the maximu…
Processes during preparation of lead/acid battery positive plates from tetrabasic lead sulfate (4BS) pastes
1993
Abstract Tthe processes studied during this investigation were paste mixing and curing. Tetrabasic lead sulfate 4BS pastes were prepared by solution and paste methods both from α-PbO and mill oxides, and the development of 4BS was carried out already during the paste mixing stage. the 4BS pastes were characterized by SEM, TEM, XRD and wet-chemical methods, and the results were compared with those obtained from the characterization of corresponding tribasic lead sulfate (3BS) pastes. The preparation method was found to be one dominating factor affecting both the morphology and structure of 4BS active masses. The selection of raw material gave an additional effect on the morphology. Additiona…
Experimental analysis of materials in proton exchange membrane electrolysis cells
2019
Abstract An accelerated supply and demand of energy has resulted in an increased need for efficient energy storage options, where storing energy in hydrogen gas emerges as one of the most attractive. In this study, a singular proton exchange membrane (PEM) electrolysis cell was designed using adequately low-cost materials, and tested using polarisation curves, cyclic voltammetry and AC impedance. A comparative study of various micro porous layer (MPL) materials was performed in an effort to find suitable options which are able to steadily operate under anodic conditions. The best performance was achieved using carbon cloth, however this material was unstable. Untreated porous titanium and n…
Effect of coatings on long term behaviour of a commercial stainless steel for solid oxide electrolyser cell interconnect application in H2 /H2O atmos…
2014
Abstract K41X (AISI 441) stainless steel evidenced a high electrical conductivity after 3000 h ageing in H 2 /H 2 O side when used as interconnect for solid oxide electrolyser cells (SOEC) working at 800 °C. Perovskite (La 1 − x Sr x MnO 3 − δ ) and spinel (Co 3 O 4 ) oxides coatings were applied on the surface of the ferritic steel for ageing at 800 °C for 3000 h. Both coatings improved the behaviour of the steel and give interesting opportunities to use the K41X steel as interconnect for hydrogen production via high temperature steam electrolysis. Co 3 O 4 reduced into Co leading to a very good Area Specific Resistance (ASR) parameter, 0.038 Ω cm 2 . Despite a good ASR (0.06 Ω cm 2 ), La …